Texas Class D Water License Test – Full Practice
Questions with Answers.
Do not work in a trench ________ feet or deeper unless it is protected from
cave-in. -<<< Correct Answer: 5 feet
Using timber, plywood, or commercial devices to support an excavation is
known as ________. -<<< Correct Answer: shoring
Shoring is not necessary if the trench walls are sloped to the maximum
allowable ________. -<<< Correct Answer: slope
Place spoil banks at least ________ feet from the trench excavation. -<<< Correct
Answer: 2 feet
Dose new mains with ________ mg/L or more of chlorine at least ________
hours. -<<< Correct Answer: 25 mg/L
24 hours
Do not place a main into service until a bacteriological sample is tested with
________ results. -<<< Correct Answer: negative
One bacteriological sample is required for each ________ feet of completed
main. -<<< Correct Answer: 1,000 feet
Flushing reduces slime and scale buildup, reduces red water complaints, brings
chlorinated water to contaminated areas, and removes ________ materials from
the system. -<<< Correct Answer: chlorine-reducing
Page 1 of 41
,Texas Class D Water License Test – Full Practice
Questions with Answers.
Closing a hydrant valve too fast can cause water ________. -<<< Correct Answer:
hammer
________ is a buildup of oxidized iron, calcium carbonate, or other chemicals in
mains. -<<< Correct Answer: Tuberculation
Factors that make water more corrosive are low pH, dissolved oxygen, and
________. -<<< Correct Answer: free chlorine
Repairing a leak under some pressure has an advantage of ________. -<<<
Correct Answer: reducing contamination risk
A _____ is a physical connection between a public water supply, and 1) another
supply of unknown or questionable quality, 2) any source that may contain
contamination, 3) any water treated to a lesser degree. -<<< Correct Answer:
cross connection
The air gap is the only cross-connection control method approved by the TCEQ
for protection against ________. -<<< Correct Answer: sewage
contamination
When storms are expected, the water utility should alert personnel, check
communications, fill gasoline tanks, check emergency equipment, fill storage
tanks, and ________. -<<< Correct Answer: isolate elevated storage
The most common pump in the water utility field is the ________ pump. -<<<
Correct Answer: centrifugal pump
Page 2 of 41
,Texas Class D Water License Test – Full Practice
Questions with Answers.
Three types of pump curve are head capacity curve, efficiency curve, and
________ curve. -<<< Correct Answer: horsepower
As the force a pump works against increases, the capacity and efficiency
________. -<<< Correct Answer: decrease
Install a _____ in a pump discharge line to prevent water from flowing back
through the pump during shutdown. -<<< Correct Answer: check valve
Common pump problems include ________ and water hammer. -<<< Correct
Answer: cavitation
The most common pump motor is the ________ motor. -<<< Correct Answer:
squirrel cage induction
The federal law regulating workplace safety is the ______. -<<< Correct Answer:
Occupational Safety and Health Act
The Texas Hazard Communication Act is known as the _____ law. -<<< Correct
Answer: "Right to Know" law
A _____ is 1) large enough to enter and do work; 2) has limited or restricted
entry or exit; and 3) is not designed for continuous occupancy. -<<< Correct
Answer: confined space
Page 3 of 41
, Texas Class D Water License Test – Full Practice
Questions with Answers.
The number one cause of death in a confined space is _____. -<<< Correct
Answer: lack of oxygen
Combustible gases include methane, hydrogen sulfide, and carbon dioxide.
(true/false) -<<< Correct Answer: false (carbon dioxide is not combustible)
_____ can adapt to conditions that would kill a human. -<<< Correct Answer:
Cockroaches
After evaluation, confined spaces are designated as _____ or _____. -<<< Correct
Answer: permit required or non-permit required
When entering a "permit required" space, personnel must wear a harness and
be attached to a ________ line. -<<< Correct Answer: retrieval line
OSHA requires an anti-fall line if a portable ladder or ________ are not used. -
<<< Correct Answer: stairs
When a vertical entry of ________ feet or more is made, the retrieval line must
be attached to a mechanical retrieval device. -<<< Correct Answer: 5 feet
Private employers, such as contractors, must follow ________ excavation and
trenching rules. -<<< Correct Answer: OSHA
When an excavation is ________ feet or deeper, a means of cave-in protection is
required. -<<< Correct Answer: 5 feet
Page 4 of 41
Questions with Answers.
Do not work in a trench ________ feet or deeper unless it is protected from
cave-in. -<<< Correct Answer: 5 feet
Using timber, plywood, or commercial devices to support an excavation is
known as ________. -<<< Correct Answer: shoring
Shoring is not necessary if the trench walls are sloped to the maximum
allowable ________. -<<< Correct Answer: slope
Place spoil banks at least ________ feet from the trench excavation. -<<< Correct
Answer: 2 feet
Dose new mains with ________ mg/L or more of chlorine at least ________
hours. -<<< Correct Answer: 25 mg/L
24 hours
Do not place a main into service until a bacteriological sample is tested with
________ results. -<<< Correct Answer: negative
One bacteriological sample is required for each ________ feet of completed
main. -<<< Correct Answer: 1,000 feet
Flushing reduces slime and scale buildup, reduces red water complaints, brings
chlorinated water to contaminated areas, and removes ________ materials from
the system. -<<< Correct Answer: chlorine-reducing
Page 1 of 41
,Texas Class D Water License Test – Full Practice
Questions with Answers.
Closing a hydrant valve too fast can cause water ________. -<<< Correct Answer:
hammer
________ is a buildup of oxidized iron, calcium carbonate, or other chemicals in
mains. -<<< Correct Answer: Tuberculation
Factors that make water more corrosive are low pH, dissolved oxygen, and
________. -<<< Correct Answer: free chlorine
Repairing a leak under some pressure has an advantage of ________. -<<<
Correct Answer: reducing contamination risk
A _____ is a physical connection between a public water supply, and 1) another
supply of unknown or questionable quality, 2) any source that may contain
contamination, 3) any water treated to a lesser degree. -<<< Correct Answer:
cross connection
The air gap is the only cross-connection control method approved by the TCEQ
for protection against ________. -<<< Correct Answer: sewage
contamination
When storms are expected, the water utility should alert personnel, check
communications, fill gasoline tanks, check emergency equipment, fill storage
tanks, and ________. -<<< Correct Answer: isolate elevated storage
The most common pump in the water utility field is the ________ pump. -<<<
Correct Answer: centrifugal pump
Page 2 of 41
,Texas Class D Water License Test – Full Practice
Questions with Answers.
Three types of pump curve are head capacity curve, efficiency curve, and
________ curve. -<<< Correct Answer: horsepower
As the force a pump works against increases, the capacity and efficiency
________. -<<< Correct Answer: decrease
Install a _____ in a pump discharge line to prevent water from flowing back
through the pump during shutdown. -<<< Correct Answer: check valve
Common pump problems include ________ and water hammer. -<<< Correct
Answer: cavitation
The most common pump motor is the ________ motor. -<<< Correct Answer:
squirrel cage induction
The federal law regulating workplace safety is the ______. -<<< Correct Answer:
Occupational Safety and Health Act
The Texas Hazard Communication Act is known as the _____ law. -<<< Correct
Answer: "Right to Know" law
A _____ is 1) large enough to enter and do work; 2) has limited or restricted
entry or exit; and 3) is not designed for continuous occupancy. -<<< Correct
Answer: confined space
Page 3 of 41
, Texas Class D Water License Test – Full Practice
Questions with Answers.
The number one cause of death in a confined space is _____. -<<< Correct
Answer: lack of oxygen
Combustible gases include methane, hydrogen sulfide, and carbon dioxide.
(true/false) -<<< Correct Answer: false (carbon dioxide is not combustible)
_____ can adapt to conditions that would kill a human. -<<< Correct Answer:
Cockroaches
After evaluation, confined spaces are designated as _____ or _____. -<<< Correct
Answer: permit required or non-permit required
When entering a "permit required" space, personnel must wear a harness and
be attached to a ________ line. -<<< Correct Answer: retrieval line
OSHA requires an anti-fall line if a portable ladder or ________ are not used. -
<<< Correct Answer: stairs
When a vertical entry of ________ feet or more is made, the retrieval line must
be attached to a mechanical retrieval device. -<<< Correct Answer: 5 feet
Private employers, such as contractors, must follow ________ excavation and
trenching rules. -<<< Correct Answer: OSHA
When an excavation is ________ feet or deeper, a means of cave-in protection is
required. -<<< Correct Answer: 5 feet
Page 4 of 41
